In this paper we present a numerical discretization of the coupled elasto-acoustic wave propagation problem based on a Discontinuous Galerkin Spectral Element (DGSE) approach in a three-dimensional setting. The unknowns of the coupled problem are the displacement field and the velocity potential, in the elastic and the acoustic domains, respectively, thereby resulting in a symmetric formulation. After stating the main theoretical results, we assess the performance of the method by convergence tests carried out on both matching and non-matching grids, and we simulate realistic scenarios where elasto-acoustic coupling occurs. In particular, we consider the case of Scholte waves and the scattering of elastic waves by an underground acoustic cavity. Numerical simulations are carried out by means of the code SPEED, available at this http URL.

中文翻译：

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基于不连续伽辽金谱元法的 3D 弹性声波传播仿真

在本文中，我们基于三维设置中的不连续伽辽金谱元 (DGSE) 方法提出了耦合弹声波传播问题的数值离散化。耦合问题的未知数分别是弹性域和声学域中的位移场和速度势，从而导致对称公式。在陈述主要理论结果后，我们通过在匹配和非匹配网格上进行的收敛测试来评估该方法的性能，并模拟发生弹声耦合的真实场景。特别地，我们考虑了 Scholte 波和地下声腔对弹性波的散射的情况。数值模拟是通过代码 SPEED 进行的，可在此 http URL 上获得。